Abstract
Patients with stroke or epilepsy face an elevated risk of subsequent strokes. This nationwide retrospective cohort study analyzed data from Taiwan's National Health Insurance Research Database (2012-2020) to compare the risk of future ischemic stroke or transient ischemic attack (IS/TIA) among patients with epilepsy and those with prior IS/TIA. Patients were categorized into four groups: epilepsy with subsequent IS/TIA (E/S), epilepsy without IS/TIA (E), IS/TIA without epilepsy (S), and neither condition (C). Incidence rates and adjusted hazard ratios for IS/TIA and mortality were assessed across groups, which included 5,606, 11,212, 11,212, and 56,060 patients. The corresponding incidence rates of subsequent IS/TIA were 0.67, 0.03, 0.41, and 0.01 per 100 person-years in the E/S, E, S, and C groups, respectively. Compared to the S group, the E/S group had a higher adjusted hazard ratio for IS/TIA (aHR 1.68, 95% CI: 1.30-2.17), whereas the E group had a significantly lower adjusted hazard ratio (aHR 0.08, 95% CI: 0.04-0.14). Mortality risk was significantly elevated in both the E/S group (aHR 1.90, 95% CI: 1.75-2.05) and the E group (aHR 1.21, 95% CI: 1.12-1.30), compared to the S group. These findings suggest that epilepsy increases the risk of subsequent IS/TIA, though to a lesser extent than prior IS/TIA. They underscore the importance of condition-specific prevention strategies and the need for further research into the mechanisms linking epilepsy and stroke risk.